What type of attack involves inserting malicious SQL statements into an entry field?

The attack that involves inserting malicious SQL statements into an entry field is known as an SQL Injection Attack. This type of attack exploits vulnerabilities in a web application's software by allowing the attacker to manipulate SQL queries that the application sends to its database. When a user submits input through an entry field, if the application does not properly validate or sanitize this input, it can allow the attacker to execute arbitrary SQL code.

By injecting SQL commands, an attacker can gain unauthorized access to data, modify or delete records, and perform various harmful operations against the database. This is particularly dangerous because it bypasses traditional security measures that are designed to prevent unauthorized access to sensitive information.

Understanding this concept is crucial for anyone in the field of network security, as mitigating SQL injection threats involves implementing secure coding practices, input validation, and database access control measures. This attack stands in contrast to the other options listed, which focus on different attack vectors and methodologies, leaving SQL injection as a specialized form of attack targeting SQL databases specifically.